1. Field of the Invention
The present invention relates to a liquid jet recording head that discharges a recording liquid as a droplet and that records information on a recording target medium.
2. Related Background Art
Electric connection sections of a flexible film wiring substrate (wiring film) of a liquid jet recording head, such as an inkjet recording head, are covered with a sealing liquid. FIG. 6 is a typical view of the electric connection sections of the flexible film wiring substrate of a conventional inkjet recording head.
In FIG. 6, reference numeral 1 denotes a plurality of recording element substrates that includes a plurality of discharge energy generation elements (not shown) which apply a discharge energy to the recording liquid and a plurality of discharge ports 6 that discharge the recording liquid, and that discharges the recording liquid by a pressure generated by the discharge energy. Reference numeral 8 denotes a supporting member onto which each of a plurality of recording element substrates 1 are fixedly attached in parallel. Reference numeral 11 denotes a flexible film wiring substrate (wiring film) that includes a plurality of wirings (not shown) electrically mounted on the plural recording element substrates 1 and transmitting an electrical signal from a recording apparatus main body (not shown) to each of a plurality of recording element substrates 1, and a wiring protection layer (resist) for protecting the wirings. Reference numeral 9 denotes a supporting plate that is fixedly attached to the supporting member 8 and that holds and fixes the flexible film wiring substrate 11. Reference numeral 18 denotes a first sealing resin coated to protect part of electric connection sections among peripheries of the plural recording element substrates 1, the plural recording element substrates 1, and the flexible film wiring substrate 11 from corrosion by the recording liquid and from a short-circuit through the recording liquid. Reference numeral 19 denotes a second sealing resin (indicated by a broken line) that covers electric connection sections between a plurality of electrode pads 7 and a plurality of lead electrodes 13 provided on the flexible film wiring substrate 11 to protect the electric connection sections from an external force generated by, for example, wiping.
Further, Japanese Patent Application Laid-Open No. H10-44441 discloses an inkjet head having dummy leads equal in shape to lead electrodes or resin reception sections equal in material to the lead electrodes arranged in four corners of an opening portion of the flexible film wiring substrate (wiring film) 11. By narrowing a gap between an inner peripheral portion of the opening portion of the flexible film wiring substrate (wiring film) 11 and each recording element substrate 1 using such dummy leads or resin reception sections, the second sealing rein is prevented from falling into this gap, and the second sealing resin can sufficiently seals the electric connection sections between the electrode pads provided on the recording element substrates 1 and the lead electrodes provided on the flexible film wiring substrate 11.
However, even with the configuration as described in Japanese Patent Application Laid-Open No. H10-44441, if a plurality of recording element substrates 1 are provided in, for example, one opening portion (device hole) of the flexible film wiring substrate 11, a gap larger than an arrangement pitch of the lead electrodes is formed between the lead electrodes connected to the electrode pads located on the outermost positions of the adjacent recording element substrates 1, respectively. In that case, the second sealing resin, which has covered the lead electrodes, may possibly be depressed to a position below the lead electrodes. If so, the electric connection sections between the electrode pads provided on the recording element substrates and the lead electrodes provided on the flexible film wiring substrate cannot be sufficiently sealed with the resin, with the result that the lead electrodes are exposed to thereby often, disadvantageously cause an electric short-circuit through the recording liquid.
Furthermore, if the dummy leads equal in shape to the lead electrodes are provided in the gaps between the flexible film wiring substrate and the recording element substrates, between the lead electrodes respectively connected to the electrode pads located at the outermost positions of the adjacent recording element substrates 1 as described in Japanese Patent Application Laid-Open No. H10-44441, then the dummy leads disadvantageously, often contact with the recording element substrates to cause a short-circuit or the dummy leads are disadvantageously, often taken for the lead wirings and connected to the respective electrode pads.